Fabry disease is a rare hereditary disorder which causes a deficiency of the enzyme a-galactosidase A. This enzyme is responsible for the breakdown and elimination of glycolipids. When a-galactosidase A is lacking, these glycolipids build up in various tissues such as the eye, liver, kidney, skin, muscle, heart, and blood vessels. The build up of glycolipds is thought to cause the clinical symptoms of Fabry disease. Patients with Fabry disease suffer from chronic damage to their kidney and heart as well as episodes of often severe pain. There is currently no specific treatment for Fabry disease available. In this study, patients with Fabry disease will receive an intravenous infusion of the enzyme a-galactosidase A or placebo every two weeks for six months.